Identifying Anions And Cations Flashcards
1
Q
How do you identify carbonate ions (CO32-)
A
Add HCL
Bubble gas through limewater
Observations: effervescence as CO2 is produced
Limewater turns cloudy
2
Q
How do you test for sulfates (SO42-)
A
Most metal sulphates are soluble except barium sulphate
Add HCl
Add barium nitrate (all nitrates are soluble)
Observations: white precipitate of BaSO4 formed
3
Q
How do you test for NH4+
A
Ammonia, NH3 is a base and therefore it accepts H+.
Ammonia becomes ammonium, NH4+ when it reacts with an acid (which donates protons).
Add NaOH to turn NH4+ to NH3
Warm to evaporate NH3 (l) to NH3(g)
Observations: damp red litmus paper turns blue
